A Study to Evaluate the Effect of GDC-4198 Alone and in Combination With Giredestrant Versus Abem… (NCT07100106) | Clinical Trial Compass
RecruitingPhase 1/2
A Study to Evaluate the Effect of GDC-4198 Alone and in Combination With Giredestrant Versus Abemaciclib and Giredestrant in Participants With Locally Advanced or Metastatic Estrogen Receptor-Positive (ER+), Human Epidermal Growth Factor Receptor-Negative (HER2-) Breast Cancer
United States, Australia, Brazil285 participantsStarted 2025-10-07
Plain-language summary
The purpose of this study is to assess the safety of GDC-4198 alone and in combination with giredestrant and also the efficacy of GDC-4198 + giredestrant versus abemaciclib + giredestrant in participants with locally advanced or metastatic ER+, HER2- breast cancer. The study consists of 2 phases: Phase Ib and Phase II. Phase Ib will evaluate the safety and pharmacokinetics (PK) of GDC-4198 alone and in combination with giredestrant. Phase II stage will compare the activity and safety of GDC-4198 and giredestrant with abemaciclib and giredestrant.
Who can participate
Age range
18 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Histologically and/or cytologically confirmed adenocarcinoma of the breast that is locally advanced or metastatic.
* Previously documented ER+ and HER2- tumor according to American Society of Clinical Oncology (ASCO)/ College of American Pathologists (CAP) or European Society of Medical Oncology (ESMO) guidelines or any national guidelines with criteria conforming to ASCO/CAP or ESMO guidelines.
* Disease progression during or after treatment with an approved cyclin-dependent kinase 4/6 (CDK4/6) inhibitor and approved endocrine therapy (ET) in the locally advanced or metastatic setting.
* Measurable or non-measurable evaluable, disease per Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1).
* Eastern Cooperative Oncology Group (ECOG) Performance Status of 0 or 1.
* Life expectancy \>= 6 months.
Exclusion Criteria:
* Advanced, symptomatic, visceral spread that is at risk of life-threatening complications in the short term appropriate for treatment with cytotoxic chemotherapy at time of entry into the study, as per national or local treatment guidelines.
* Have received more than one-line of therapy for locally advanced or metastatic disease.
* Have received prior chemotherapy for metastatic breast cancer.
* Treatment with an approved oral ET within 7 days prior to initiation of study drug; treatment with fulvestrant or an approved CDK4/6 inhibitor within 21 days prior to initiation of study drug.
* Malabsorption condition or other g…
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Phase Ib: Incidence and Severity of Adverse Events (AEs)
Timeframe: Up to 36 months
2
Phase Ib: Number of Participants With Dose-Limiting Toxicity (DLTs)
Timeframe: From Day 1 to Day 28 of Cycle 1 (1 cycle=28 days)
3
Phase II: Progression-free Survival (PFS)
Timeframe: Up to 36 months
Trial details
NCT IDNCT07100106
SponsorGenentech, Inc.
Sponsor typeINDUSTRY
Study typeINTERVENTIONAL
Primary completion2028-08-31
Contact for this trial
Reference Study ID Number: GO46021 https://forpatients.roche.com/